Assembly Language Quiz

Which assembler directive is typically used to declare an 8-bit variable?

• DW

• DD

• DB

• DQ

What does the DW directive allocate in memory?

• 1 byte

• 2 bytes

• 4 bytes

• 8 bytes

Which instruction uses an immediate constant rather than a memory location?

• MOV AX, 1000h

• MOV AX, [1000h]

• MOV DS, AX

• MOV [1000h], AX

Consider the declaration: asm Copy Edit MYBYTE DB 0x55 What is the size and value of MYBYTE?

• 16-bit, 55h

• 8-bit, 55h

• 32-bit, 55h

• Not enough information

Which directive is used to define a constant that cannot be modified during program execution?

• CONST

• EQU

• DEFINE

• SET

The Data Segment (DS) register is used in assembly language to:

• Point to the stack area

• Reference code

• Locate data variables

• Manage I/O operations

Accessing a variable using its label, as in: asm Copy Edit MOV AL, MYVAR This mode is known as:

• Immediate addressing

• Register addressing

• Direct addressing

• Indirect addressing

Given the line: asm Copy Edit NUM DW 1234h How many bytes are allocated for NUM?

• 1 byte

• 2 bytes

• 4 bytes

• 8 bytes

In many assembly languages (e.g., NASM), which directive is used to reserve uninitialized memory (in the BSS segment) for a variable?

• DB

• RESB

• DW

• DCB

What is the difference between DB and DD directives?

• DB reserves 1 byte; DD reserves 2 bytes.

• DB reserves 1 byte; DD reserves 4 bytes.

• DB reserves 2 bytes; DD reserves 4 bytes.

• DB reserves 4 bytes; DD reserves 8 bytes.